First report ofOvipleistophora ovariaeandO. diplostomuriin China provides new insights into the intraspecific genetic variation and extends their distribution

Abstract

Microsporidia of the genus Ovipleistophora are generally parasites of fishes and aquatic crustaceans. In the current study, Ovipleistophora diplostomuri and O. ovariae were firstly reported from Culter alburnus and Xenocypris argentea and Parabramis pekinensis, respectively. Both of them exclusively infected fish ovary and were morphologically, ultrastructurally and genetically characterized. Sporogony occurred in direct contact with the host cell cytoplasm and sporophorous vesicles were not observed for the new isolates of these two Ovipleistophora species. Spores of O. ovariae were for the first time observed to be dimorphic. Genetic analysis indicated that the genetic variation in the ITS and LSU sequences was distinct among between-host O. diplostomuri isolates. High sequence variation in ITS sequence suggests that it can be a reliable molecular marker to explore the population genetics of O. diplostomuri. This is the first report of these two Ovipleistophora species in China which extends their host and geographical range.

Morphological characterization and genetic diversity of a new microsporidium, Neoflabelliforma dubium n. sp. from the adipose tissue of Diaphanosoma dubium (Crustacea: Sididae)

“…Liebermannia (Sokolova et al, 2009), Neoperezia (Issi et al, 2012) and Ovipleistophora (Weng et al, 2021b), suggesting that presence of sporophorous vesicles referred from the type species maybe not be the r e l ia b l e t a x o n o m i c c r it e r i o n o f t h e s e g e n e r a d u e t o morphological plasticity.…”

Intraspecific genetic diversity of the fish-infecting microsporidian parasite Pseudokabatana alburnus (Microsporidia)

“…Therefore, a question will be raised whether these 7 East Asian minnows-infecting microsporidians are conspecific or of different taxa. Intraspecific morphological plasticity has been intensively reported for many fish microsporidians, like Ovipleistophora ovariae ( Weng et al, 2021a ), O. diplostomuri ( Weng et al, 2021a ) and Pleistophora hyphessobryconis ( Li et al, 2012 ). Although the spore size and spore wall thickness of P. alburnus in current isolates from the ovary differ from those in previous isolates from the liver, the internal structure characteristics of the spores are consistent, demonstrating that few intraspecific morphological variation among P. alburnus isolates was found here.…”

“…The ribosomal internal transcribed spacer region (ITS) and the large subunit ribosomal RNA (LSU rDNA) has been increasingly employed to resolve this issue for they possess sufficient variable loci ( Bell et al, 2001 ; Lom and Nilsen, 2003 ). Furthermore, referring to ITS and LSU sequences comparison, intraspecific genetic variation was identified in Ovipleistophora diplostomuri and several Loma species ( Brown et al, 2010 ; Weng et al, 2021a ). If this intraspecific genetic variation is linked with possible phenotypic changes remains unknown, however, intraspecific differences in ultrastructure of spores was previously found in Pleistophora hyphessobryconis ( Li et al, 2012 ).…”

Microsporidia: a new taxonomic, evolutionary, and ecological synthesis

“…In some cases, studies use a transmission experiment to determine whether a microsporidian parasite can be passaged from one organism to another, either through feeding or cohabitation [79]. In other cases, observation or molecular diagnosis of a microsporidian is used to explore host range [76,80].…”

“…An emerging area of interest includes the process of trophic transmission across highly divergent host species [34,42,[80][81][82]. The Ovipleistophora diplostomuri conundrum involves a sequencing effort to look for this parasite in crustacean and fish hosts.…”